GUIDE
FDA 510(k), De Novo and PMA: how the three routes differ
Most United States market-entry questions come down to which premarket route a device is likely to sit in, and what that route expects you to demonstrate. The three principal routes ask for different things, and the choice between them usually follows from classification and from whether a suitable predicate device exists.
PUBLIC SOURCES · UNITED STATES (FDA) · NOT A PATHWAY DETERMINATION
01
What each route asks you to demonstrate
The three routes are not tiers of effort applied to the same question. Each asks a structurally different question, which is why the evidence expected under one route does not translate cleanly to another.
- 510(k) PREMARKET NOTIFICATION
- That the device is substantially equivalent to a legally marketed predicate device in intended use and technological characteristics, or that any differences do not raise different questions of safety and effectiveness. The comparison, not the device in isolation, carries the submission.
- DE NOVO CLASSIFICATION REQUEST
- That a device with no suitable predicate can be reasonably assured of safety and effectiveness through general and special controls, so it can be classified into Class I or Class II rather than defaulting to Class III.
- PREMARKET APPROVAL (PMA)
- That there is valid scientific evidence providing reasonable assurance of safety and effectiveness for the device itself, generally including clinical data. This is the most evidence-intensive of the three and applies to most Class III devices.
02
What usually decides the route
In practice the route follows from a small number of upstream facts, and most of them are set by decisions the team has already made about the product rather than by the submission strategy.
- INTENDED USE STATEMENT
- A change in intended use or indications for action can move a device out of the range covered by an otherwise similar marketed device, which affects whether the 510(k) comparison is available at all.
- CLASSIFICATION AND PRODUCT CODE
- The regulation and product code a device is likely to fall under carry their own controls, exemptions and expectations. Two devices that look similar in marketing terms can sit under different codes.
- AVAILABILITY OF A PREDICATE
- Where there is no legally marketed device on which to base substantial equivalence, a De Novo request may be available if general controls alone, or general and special controls, can provide reasonable assurance of safety and effectiveness. PMA generally applies to Class III devices.
- TECHNOLOGY AND RISK PROFILE
- Novel mechanisms of action, life-supporting or life-sustaining function, or significant risk of illness or injury push a device toward the more evidence-intensive end of the range.
03
Where teams get caught out
The recurring pattern is not a misread rule. It is a pathway assumption that was reasonable when the product was smaller in scope, and was never revisited as the intended use widened.
A second common pattern is a predicate chosen for technological similarity while the intended use drifts, which weakens the comparison the whole submission rests on. Timing matters too: evidence planned for one route is not always usable under another, so a late route change can force testing, evidence and documentation plans to be revisited.